The National Center for Rehabilitation Engineering (NCRE)

The Functional Electrical Stimulation experiments, one of many efforts undertaken by the National Center for Rehabilitation Engineering (NCRE), resulted in a Wright State University student, Nan Davis’ graduation walk in June 1983.  Ms. Davis was the first person to walk computer-aided by electro-stimulation of the muscles.  This widely publicized event gained national attention to Wright State University

The technology that enabled Nan Davis to take her historic graduation walk was based on a computer program which gave the commands to electrically stimulate 10 separate muscle groups to move. The general smoothness of the walking movement was obtained using a feedback system which transmits information about muscle and joint position, relative to the desired direction of movement. The feedback system uses sensors at the waist, knees and ankles.

A safety harness was part of Petrofsky’s first walking experiments. Since no one at the time had ever had a paraplegic or quadriplegic walk they didn’t know if the bones or muscles could sustain full body weight. To ensure the safety of participants, Petrofsky used a modified parachute harness, offset by weights, so the load of the subject’s body could be gradually introduced.

The harness, worn like a parachute harness, was attached to an overhead support platform. The weights offset the body weight so less than half the subject’s body weight would be applied to the joints. As the subject’s bones and joints thicken and strengthen from the walking, an increasing percentage of the weight would be allowed, until the joints could support the full body weight.

Similar efforts used Functional Electrical Stimulation to help stimulate movement in other areas of the body, such as the arms.

The leg trainer chair enabled a person with paralyzed legs to lift weights with the assistance of a computerized electrical stimulation-feedback system. The device was developed at Wright State University’s National Center for Rehabilitation Engineering and actively used in their physical therapy program for paralyzed people. The program was intended to aid in the rebuilding of muscles, bones and cardiovascular systems of people who have paralysis.